package main

import (
	"fmt"
)

type Reader1 interface {
	ReadBook1()
}

type Writer1 interface {
	WriterBook1()
}
type Book12 struct {
}

func (this *Book12) ReadBook1() {
	fmt.Println("Read a Book11111111111")
}

func (this *Book12) WriterBook1() {
	fmt.Println("Write a Book22222222")
}

func main() {
	b := &Book12{}

	var r Reader1
	r = b
	r.ReadBook1()

	var w Writer1
	w = r.(Writer1)
	w.WriterBook1()
}
